The present invention relates to an addition-reacting silicone pressure-sensitive adhesive composition which can be cured to give a pressure-sensitive adhesive.
Silicone pressure-sensitive adhesives have an excellent adhesive strength, tack, and cohesive strength, which are the properties required of a pressure-sensitive adhesive. In addition, they also have the heat resistance, cold resistance, and electrical properties, etc., characteristic of silicones, and so are widely used for e,lectric-insulating tape, which must be highly reliable, and for various pressure-sensitive products which must be resistant to hot and cold.
In general, organoperoxide-curing compositions are used as silicone pressure-sensitive adhesive compositions. A composition which cures by the addition reaction between alkenyl-containing organopolysiloxane and organopolysiloxane having silicon-bonded hydrogen atoms has also been disclosed in Japanese Patent Publication No. 54-37907 [37,907/79].
However, said organoperoxide-curing compositions must be cured by heating at temperatures of at least 130.degree. C. in order to convert them into the pressure-sensitive adhesive. As a consequence, they cannot be used with poorly heat-tolerant substrates.
At the same time, the aforementioned addition-curing composition suffers from variations in its adhesive strength due to the difficulty of forming a film with good physical properties on the substrate.